Electrical starting system for internal combustion engines



Feb. 16, 1932. H. DJSTECHER 5,7

ELECTRICAL STARTING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Sept. 12, 1929 INVENTOR H'D-STECHER ATTO RN EY Patented Feb. 16, 1932 "UNITED STATES PATENT OFFICE HENRY D. STECHEB, OI LAKEWOOD, OHIO, ASSIGNOR TO ALBERT J. WEATHEEHELD, m,

OF CLEVELAND, OHIO ELECTRICAL STARTING SYSTEM FOR INTERNAL COMBUSTION Enomm Application filed September 12, 1929. Serial No. 392,153.

This invention pertains to an electrical starting s stem for internal combustion engines, an is an im rovement especially applicable to automobiles or other motor driven vehicles in which an electric starting motor, storage battery, and generator, are used. The engine may include a power transmitting clutch controlled by a foot pedal as usual; an electric starting motor geared to the engine by such known means as the so-called Bendix drive; and also an electric generator driven by the engine havin a cut-out relay adapted to keep the storage attery in a charged condition for starting, ignition, and lighting purposes. M object in general,'is to utilize such known evices in circuit with an electro-magnetic switch, substantially as hereinafter described, whereby the engine may be started, preferably by manipulating the clutch pedal, and then when the engine is operating under its own power, using the pressure or voltage of the generator to enervate the electro-magnetic switch to stop the starting motor. In a preferred form of the invention, an electro-magnetic switch is used to make and break the battery circuit for the starting motor, and the clutch pedal is utilized to make and break a controlling circuit which includes the coil of the electro-magnetic switch and also the generator windings. In operation, when the operator of the vehiele depresses the clutch pedal and throws out the engine clutch, the controlling circuit is closed and the electro-magnetic switch is energized, thereby starting the engine by closing the starting motor circuit. The voltage of the enerator depends upon the speed at which t e engine is driven, all other factors remaining constant, and at low engine speed the voltage is not high enough to charge the battery or to affect the electro-magnetic switch adversel However, when starting of the engine as been accom lished, the speed of the engine increases an at a given s ed the volta e of the enerator equals the elrctromotive orce of t e battery. Under that condition the electro-magnetic switch will be deprived of its force andpaused to open, thereby breaking the circuit for the starting motor and stopping the same. Also,

as long as the engine and generator are running normally, the electro-magnetic switch will be rendered feeble or impotent, and the starting motor cannot be operated, should the pedal be depressed to its full extent and the pedal switch closed. However, should the engine stall and stop, the original conditions will be resumed, andthe engine can be started again in the way described.

A an; in the accompanying drawings, Fig. 1 1s a w sectional view of a portion of an automobile, showing an internal combustion engine and an electrical starting system therefor constructed and arranged according to my invention, and Fig. 2 is a diagram of the elece6 tric circuits and parts therein. As thus delincated the invention includes an internal combustion engine E, having an electric starting motor M, and an electric generator G operatively geared thereto as customarily.

engine E, and also a second circuit 3 con- 00 necting the coil or winding 4 of an electromagnetic switch A, with a pedal operated switch P, and the windings of generator G, including'the windings 5 of the cut-out relay R which is ordinarily associated with or 86 forms a part of the generator.

Thus, magnet coil 4, and pedal switch P are connected in series with the windings of generator G and relay coil 5, and circuit 3 may be closed and opened by foot pedal P, at the election 0 of the operator. When ignition switch S is closed, and circuit 3 is also closed by pedal switch P, the elcctro-magnetic switch A is energized, assuming engine E is not running under its own power. switch P closes motor circuit 6 and starts motor M and en ine E, thereby also starting g nerator G. Grdinarily, w en engine starts and comes up to speed, the gearing for the starting motor is automatically discon- The starting motor M,

The closing of pedal nected, using the customary self-releasing starting mechanisms. The operator ma still continue to press pedal P and hold switc P closed, inasmuch as pro sion is made to use the voltage of generator e to render coil 4 inactive and open the electro-magnetic switch A, thus cutting ofi the battery current from motor M. I

The principal function of generator Gris to keep storage batter B in a charged condition. In charging t 'e battery the current must flow in a reverse direction to that in discharging. To accomplish this, the voltage of the generator must be somewhat hi her than the back pressure or electromotive force of the battery. in startin or at 'low engine speed, the voltage is not high enough to chargethe batteiy. When the engine is stopped entirely, the voltage of the generator falls to zero, due to the low resistanceof the armature of the generator, and the battery can be caused to discharge through circuit 3 and the generator windings. For that reason the elcctro-magnetic switch coil 4 is connected in series with the generator so that it may be cncrgizedby the battery current in starting'operations. To prevent discharge of thebattery when the engine is not running nor being started, the cut-out relay R is inserted into the charging line 7 between the generator and the battery;

Thus, the main function of cut-out relay R is to automatically close a charging circuit 7- between the generator and battery when the pressure of the generator is slightly in excess of the back pressure or electromotive force of the battery. When the pressure of the generator dropsslightly'below that of the battery (due to low engine speed), the switch or. cut-out relay automatically opens charging circuit 7, thus preventing the battery from ischarging bac through this v circuit and the generator windings.

When the en inc is running under its own power, no malunction or ill effect will arise should the operator depress pedal P and close switch P, irrespective of the speed of generator G. Thus if the generator is running at a speed sufiicient to charge the battery the relay It will be closed, thus providinga direct path over circuit 7 to the battery for the generator current. Practically no gencrntor current will then flow back to the battery through circuit 3, duet-o the resistance of electro-magnetic coil 4. On the other hand if the generator voltage is not suflicient to charge the battery, voltage is created nevertheless in opposition to that of the battery with such neutralizing efiect that electromagnetic switch A will not close but will be held open by the tension of a spring 8. Starting can be effected when the engine is entirely stopped or stalled by simply depressing the clutch pedal P which causes the battery current to close the single'electromagnetic switch A. Then, as the generator G and cut-out relay R are in the same circuit as this electro-magnetic switch they in themselves prevent the starting motor .from being operated when the engine is running at idling or higher speeds.

Pedal P may be operated to throw out the clutch without actuating switch P, and to;

cuit 3 is effected solely by the ignition switch- S, I prefer to use an ignition switch embodying two so arate contacts 8 and 9, respectively, for t e ignition circuit 2 and the controlling circuit 3, substantially as delineated in Fig. 2. In that case when ignition switch S is opened a break is effected between the ignition circuit 2 and the controlling circuit 3, and enerator G is cut off entirely from the ignition circuit. Otherwise under certain conditions the engine would continue to run on the generator current flowing over circuits 3 and 2, assumin pedal switch P to be closed or omitted. referably a pedal controlled switch is used, as an inexperienced or careless operator cannot start the engine Without throwing out the clutch or with the gears in mesh'. Should the motor stall or stop in trafiic,or on a hill or up-grade,

starting can be effected by disengaging the clutch with one foot while controlling the brake with the other foot and operating the throttle controls on the steering wheel by hand.

What I claim, is:

l 1. In an electrical starting and ignition system for internal combustion engines, an engine having an electric starting motor and an i ition circuitand electric generator operatively connected therewith; a cut-out re-.

lay for said generator in a chargingcircuit for said battery; a storage battery and a circuit therefor, including said starting motor and a starting and stopping switch; and a controlling circuit for said switch connecting said battery and generator, including'a magnetic controlling device for said switch and a dered impotent by the voltage of the generator when the engine is running.

2. In a system susbtantially as herein described, an internal combustion engine having an electric generator, and an electric starting motor operatively connected therewith, the generator having a battery cut-out relay; a storage battery electrically connected in a charging circuit with said generator and relay; an ignition circuit for said engine; astarting circuit having a main switch to control starting and stopping of said electric motor; and a controlling circuit, including an electro-magnet and winding for operating said mainswitch,the generator and relay windings, said battery, and a manually operable double contact, single blade switch for electrically connecting said ignition and controlling circuits with the battery and capable of completely breaking the ignition and controlling circuits in respect to each other as well as completely breaking each respective circuit to prevent feed back of the generator current to the ignition circuit when the battery current is cut off by said switch.

3. 'In an electrical starting and i ition system, an internal combustion engine, an ignition circuit, a battery therefor, an electrically operable starting motor and an electrically operable generator operatively connected therewith, a cutout relay for said generator in a charging circuit to said battery a circuit including said starting motor and an electromagnetic switch subjected to energization by said battery, a controlling circuit for said magnetic switch including a manually operable doubde contact switch, one of said contacts being laced in the ignition circuit and the other of said contacts being placed in said controlling circuit, said ignition and controlling circuit being electrically connected when said switch is closed and each circuit respectively being completely broken and separated each from the other when said switch is open.

In testimony whereof I aflix my signature.

I-[ENRY D'. STECHER. 

